A new computer chip lithography method under development at Rochester Institute of Technology has led to imaging capabilities beyond that previously thought possible.
Leading a team of engineering students, Bruce Smith, RIT professor of microelectronic engineering and director of the Center for Nanolithography Research in the Kate Gleason College of Engineering, developed a method—known as evanescent wave lithography, or EWL—capable of optically imaging the smallest-ever semiconductor device geometry. Yongfa Fan, a doctoral student in RIT’s microsystems engineering Ph.D. program, accomplished imaging rendered to 26 nanometers —a size previously possible only via extreme ultraviolet wavelength, Smith says. By capturing images that are beyond the limits of classical physics, the breakthrough has allowed resolution to smaller than one-twentieth the wavelength of visible light, he adds.
The development comes at least five years sooner than anticipated, using the International Technology Roadmap for Semiconductors as a guide, Smith says. The roadmap, created by a consortium of industry groups, government organizations, universities, manufacturers and suppliers, assesses semiconductor technology requirements to ensure advancements in the performance of integrated circuits to meet future needs.
Evanescent wave lithography is an “enabling technology” permitting better understanding of how building blocks are created for future microelectronic and nanotechnology devices—the technology that consumers will use over the next five to 10 years, Smith explains.
For clarity, chip lithography is the process of making computer chips. The smaller you can get, the faster the resulting chip will be.
CRNano also reports on this, and provides a layman explanation:
The "diffraction limit" used to be thought of as a fundamental barrier: you couldn't do anything with light that involved distances smaller than half a wavelength. Imagine that you're jumping rope while dancing around and using the rope's impact on the ground to sweep patterns in the dust. By just spinning the rope around yourself, you can't make patterns that are much narrower than you are.
But if you can shake the rope in intricate, carefully controlled patterns instead of just swinging it around, you can make it touch the ground in smaller and more controlled areas. Similarly, if you send the light through very carefully calculated masks, you can make the energy -- over a very short distance -- take on patterns that are quite a lot more intricate than a simple wave of light.
The CRNano post is ended with a keen insight and an interesting question:
Another rule has been broken by this work -- this one not a "rule" of physics, but a human prediction. As the article explains, evanescent wave lithography wasn't expected to be developed for another five years. Technology seems to have a habit of doing that, these days.
So how long until we see the first positionally controlled, atomically precise diamond fabrication?
Technological progress is accelerating exponentially. Our society will be transformed as techno-revolutions start following each other up faster and faster. The implications will be vast.
Another link to the same story (but more detailed) can be found here.